Novel process for olefin polymerization

ABSTRACT

This invention is directed to a novel process for preparing copolymers of ethylene and certain alpha olefins (including terpolymers with dienes) by reaction in the presence of vanadium and titanium catalysts together with aluminum cocatalysts.

United States Patent Wagensommer [151 3,678,019 [451 July 18,1972

[541 NOVEL PROCESS FOR OLEFIN POLYMERIZATION [72] Inventor: Joseph Wagensommer, Westfield, NJ.

[73] Assignee: Esso Research and Engineering Company [22] Filed: March 16, 1970 [2]] Appl. No.: 20,121

[52] US. Cl. ..260/80.78, 260/882 R, 252/429 B,

. 252/429 C [5 l] Int. Cl. ..C08f 15/40 [58] Field of Search ..260/80.78, 88.2; 252/429 B,

3,260,708 7/1966 Nana ..260/79.5 3,390,141 6/1968 Richards ..260/88.2 3,5 67,653 3/1971 Wagensommer ..252/429 Primary Examiner-Joseph L. Schofer Assistant Examiner-Roger S. Benjamin Attorney-Chasm and Sinnock and Harold Einhorn [57] ABSTRACT This invention is directed to a novel process for preparing copolymers of ethylene and certain alpha olefins (including terpolymers with dienes) by reaction in the presence of vanadium and titanium catalysts together with aluminum cocatalysts.

9 Claims, No Drawings 1 NOVEL PROCESS FOR OLEFIN POLYMERIZATION BACKGROUND OF THE INVENTION This invention relates to a process for preparing polymeric compositions. More specifically, it relates to a novel process for producing polymers particularly characterized by their improved properties.

As is well known to those skilled in the art, copolymers of ethylene and higher alpha olefins such as propylene with other polymerizable monomers have been prepared. Typical of these other monomers may be non-conjugated dienes such as 1,4-hexadiene or S-ethylidene-Z-norbornene. It has, however, been found that many prior art polymers so prepared have been characterized by low rates of extrusion and have tensile strengths which have not been as high as desired.

It is an object of this invention to provide a process for preparing a copolymer of ethylene, a higher alpha olefin, and preferably a non-conjugated alkadiene.

It is another object of this invention to provide a polymer characterized by improved properties.

Other objects will be apparent to those skilled in the art on inspection of the following description.

SUMMARY OF THE INVENTION In accordance with certain of its aspects, the novel process of this invention for preparing a copolymer of ethylene and a C to C higher alpha olefin may comprise:

a. forming a charge mixture of ethylene and a C higher alpha olefin;

b. forming, in an aromatic hydrocarbon solvent in the absence of cocatalyst, a catalyst mixture consisting essentially of VX, wherein X is halide having an atomic number greater than 9, and Ti(OR) wherein R is a hydrocarbon moiety, thereby forming a catalyst mixture;

. contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst mixture in said aromatic hydrocarbon solvent and of (ii) a compound R' A- IY as cocatalyst, wherein R is a hydrocarbon moiety, is an integer l-3, and Y is a halide having an atomic number greater than 9, thereby forming a copolymer of ethylene and a C C, alpha olefin; and

d. withdrawing said copolymer as product.

to C

DESCRIPTION OF THE INVENTION The ethylene used in practice of this invention as first monomer may typically be purified commercially available ethylene of greater than 99.98 percent purity, typically 99.98 percent to 99.999 percent, say 99.99 percent. It may contain less than 0.02 percent, typically 0.001 percent to 0.02 percent, say 0.01 percent nonolefinic impurities and less than 0.001 percent, say 0.0001 percent to 0.005 percent water.

The higher alpha olefin, also called a terminal olefin, which may be used in the practice ofthis invention as a second monomer, may be a purified commercially available C to C olefin having a purity of greater than 99.98 percent, typically 99.98 percent to 99.999 percent, say 99.99 percent. It may contain less than 0.02 percent, say 0.001 percent to 0.02 percent, say 0.01 percent nonolefinic impurities and less than 0.001 percent, say 0.000] percent to 0.0005 percent water. Nonpolar impurities, such as ethane or other hydrocarbons, may be present, but for best results, polar compounds such as oxygen, water, carbon monoxide, carbon dioxide, etc., may be maintained at or below the indicated low level in the ethylene and alpha olefin field.

The higher alpha olefins having three to ten carbon atoms may be designated by the formula R'CI-I CH wherein R is hydrocarbon and typically alkyl including cycloalkyl. Alpha olefins may include typically:

TABLE I propene butene-l pentene-l 3-methyl butene-l hexene-l 3-methyl pentene-l 4-methyl pentene-l heptene-l 3-methyl hexene-l 4-methyl hexene-l S-methyl hexene-I 3-ethyl pentene-l octene-l 3-methyl heptene-l 4-methyl heptene-l S-methyl heptene-l 6-methyl heptene-l 3-ethyl hexene-l 4-ethyl hexene-l 3-propyl hexene-l decenel The preferred higher alpha olefins may be propylene. i.e.. propene.

The non-conjugated diolefins which may be third monomer components of the copolymers of this invention may preferably include those having five to 14 carbon atoms. Typical of the non-conjugated diolefins may be the following:

A. Straight chain acyclic dienes such as: l,4-hexadiene; 1,6-

octadiene.

B. Branched chain acyclic dienes such as: S-methyl 1,4-hexadiene; 3,7-dimethyl, 1,6-octadiene; 3,7-dimethyl 1,7-octadiene; and the mixed isomers of dihydro-myrcene, and dihydro-ocimene.

C. Single ring alicyclic dienes such as: l,4-cyclohexadiene;

l,5-cyclo-octadiene; and l,5-cyclododecadiene.

D. Multi-ring alicyclic fused and bridged ring dienes such as: tetrahydroindene; methyltetrahydroindene; dicyclopentadiene; bieyclo (2,2,l) hepta 2,5-diene; alkenyl, alkylidene, cycloalkenyl and cycloalkylidene norbornenes such as S-methylene-Z-norbornene (MNB), S-ethylidene-Z-norbornene (ENB), S-propenyl-Z-norbornenc, 5-isopropylidene-2-norbornene, 5-(4-cyclopentenyl)-2- norbornene; 5-cyclohexylidene-Z-norbornene.

The preferred third monomer may be 5-ethylidene-2-norbornene (ENB).

Formation ofthe novel copolymers of this invention may be effected by forming a mixture of the monomer components containing the following components by weight, these being per parts ofsolvent:

Mixtures of these monomers may be used, i.e., more than one alpha olefin and/or more than one diolefin may be employed. It will be noted that when only ethylene and higher alpha olefin are present, the product may be a 2-component polymer; when the diolefin is present, the copolymer is a terpolymer. Other compatible components, including those which are copolymerizable to form tetrapolymers, may be present.

The monomer mixture may be polymerized (either batchwise or continuously) in the presence of a catalyst composition containing catalyst and cocatalyst. Preferably, the catalyst composition may consist essentially of VX, wherein X is halide having an atomic number greater than 9 and Ti(OR),, wherein R is a hydrocarbon moiety. In the component VX X may typically be chlorine, bromine, or iodine, and most preferably chlorine. The preferred composition may be vanadium tetrachloride, VCI

In the catalyst composition, the compound Ti(OR), may be one wherein R may be a hydrocarbon moiety, typically alkyl, aryl, alkaryl, and aralkyl. When R is alkyl, it may be methyl, ethyl, propyl, i-propyl, n-butyl, i-butyl, t-butyl, hexyl, cyclohexyl, octyl, etc. When R is aryl, it may be phenyl, naphthyl, etc. When R is alkaryl, it may be tolyl, xylenyl, etc. When R is aralkyl, it may be benzyl, B-phenyl ethyl, etc. The R group may be inertly substituted, i.e., it may bear a substituent which does not react with the other components of the process or interfere with the reaction. Typical inert substituents may include halogen, aryl, alkyl, etc. Typical inertly substituted R radicals may include chlorophenyl, 2-ethyl-hexyl, methylcyclohexyl, etc. All the R groups in a particular compound need not be the same; preferably, however, they may be the same. Preferably, R may be alkyl, and more preferably, lower alkyl having one to carbon atoms and, most preferably, butyl.

Preferably, the catalyst mixture may be formed by mixing 1 to 10, say 2 moles of VX with 0.5 to 50, say 1.0 moles of Ti(OR) The preferred catalyst composition may consist essentially of 2 moles of vanadium tetrachloride VCL, and 1 mole of tetrabutyl titanate Ti( OBu),

It is a feature of the process of this invention that the catalyst mixture be formed in an aromatic hydrocarbon solvent, A. Typically, aromatic hydrocarbon solvent A which may be employed may include benzene, including aromatic derivatives thereof. Typical illustrative solvents which may be employed may be benzene, toluene, o-xylene, m-xylene, pxylene, ethylbenzene, mesitylene, etc. Commercial mixtures of these aromatic hydrocarbons may be employed. The preferred compositions which may be used as aromatic hydrocarbon solvents may be those containing less than about 5 to percent, say 10 percent of non-aromatic hydrocarbons. Commonly, the solvent employed may contain less than 10 percent aliphatic hydrocarbons. Commercially available aromatic hydrocarbon solvents may be employed, including those sold as benzene, toluene, and xylene and which are substantially free of water and polar compounds.

The preferred aromatic hydrocarbon solvent may be benzene, preferably as commercially available having a purity of 95-99 percent. It will be apparent to those skilled in the art that the aromatic hydrocarbon solvent which may be employed should be substantially free of materials which will react with other components in the system, especially water, oxygenated compounds, etc.

In carrying out the process of this invention, the catalyst components may be added to 100 parts of aromatic hydrocarbon solvent typically at 10 to 80 C., say C. Typically, there may be added 0.2 to 0.8, say 0.5 parts of VX, and 0.2 to

0.8 parts, say 0.44 parts of Ti (OR) to form a mixture, and

preferably a solution, in the aromatic hydrocarbon solvent, containing 0.4 to 1.6 parts, say 1.2 parts total of catalyst mixture.

it is a feature of the novel process of this invention in its preferred aspects that the catalyst mixture consisting essentially of VX and Ti(OR) be formed in the aromatic hydrocarbon solvent in the absence of the aluminum cocatalysts used during the polymerization reaction. In practice of the preferred embodiment, the catalyst mixture (of VX and Ti(OR),,) will not come into contact with the aluminum cocatalyst prior to the in situ reaction in the reaction zone.

Presence ofthe aluminum cocatalyst composition in or with the aromatic hydrocarbon solvent prior to the addition thereto and reaction therein of the vanadium and titanium components of the catalyst mixture may effectively substantially reduce the activity of the catalyst composition in terms of the number of pounds of product polymer produced per pound of catalyst used if the preferred sequence is not followed. Furthermore, blending of the aluminum cocatalyst with the aromatic hydrocarbon solution of the catalyst complex may also significantly reduce the yield of desired product.

It is also a feature ofthe novel system of this invention that when the vanadium and titanium components of the catalyst mixture are added to the aromatic hydrocarbon solvent, substantial heat of reaction may be observed, indicating the formation of a new catalytic species by chemical reaction. As is well known to those skilled in the art, evolution of heat of reaction and formation of new catalytic species is not a feature of reported prior art techniques; and it may be the presence of this novel composition which imparts to products and process ofthis invention at least some oftheir unusual characteristics.

In accordance with certain of its aspects, this invention is directed to a polymerization catalyst composition comprising a complex VX ,'bTi(OR) wherein X is halide having an atomic number greater than 9, b is 0.1-5.0, typically about 0.5, and R is a hydrocarbon moiety dissolved in an aromatic hydrocarbon solvent. The complex formed in the presence of aromatic hydrocarbon A may be obtained as a complex VX -b- Ti(OR),,'nA in an excess of solvent-complexing agent A. n may typically be a small number 0.5-3.0, and preferably 1. The preferred complexes may be VC1,-Ti(OBu) -C H VCl -Ti(OBu)C4-C H CH VCl,-Ti(OBu).,-C H C H etc.

The aluminum cocatalyst compound which may be used in the practice of the process of this invention may be a compound R AIY wherein R is a hydrocarbon moiety, a is an integer l-3, and Y is a halide having an atomic number greater than 9. The hydrocarbon moiety R may be selected from the same group as that from which hydrocarbon moiety R may be selected. The preferred R moiety may be ethyl. Preferably a is 2. Y may be a halide, typically chloride, bromide or iodide and, most preferably, chloride. The preferred aluminum cocatalyst may be diethyl aluminum chloride.

The relative amounts of the catalyst and the cocatalyst in the catalytic mixture used in the process may be such that the molar ratio of aluminum compound to the vanadium-titanium complex may be 0.5-50, preferably 2-20, say 10.

Polymerization may be effected by passing 0.1 to 10, say 2.5 parts of ethylene, 0.1 to 20, say 6.2 parts of alpha olefin, typically propylene, and 0 to 1.0, say 0.17 parts of diolefin third monomer, typically S-ethylidene-Z-norbornene, ENB, when employed, into 100 parts of liquid inert solvent diluent reaction medium containing catalyst and cocatalyst in catalytic amounts, i.e., 0.00050.05, say 0.01 parts of catalyst and 0.00l-0.20, say 0.05 parts of cocatalyst per 100 parts of reaction medium. The nonreactive reaction medium may be an aromatic hydrocarbon such as toluene, a saturated aliphatic hydrocarbon such as heptane, cycloaliphatics such as cyclohexane, or a halohydrocarbon such as tetrachloroethylene. All steps in this reaction should preferably be carried out in the absence of oxygen, moisture, carbon dioxide or other harmful materials. Preferably, all reactants and catalysts may be pure and dry and blanketed with inert gas such as nitrogen or argon.

In the preferred embodiment the nonreactive reaction medium may preferably be the same as the aromatic hydrocarbon solvent in which the catalyst mixture has been formed. If not the same material, it will preferably be one which is compatible, e.g., totally miscible with the reaction medium.

In the preferred embodiment, the polymerization reaction may be carried out by separately feeding to the polymerization step the charge mixture of ethylene and higher alpha olefin together with diolefin, when used, the cocatalyst, and the aromatic hydrocarbon solvent containing the catalyst. During polymerization, the reaction mixture may be agitated and maintained at temperatures of 40 to 200 C., say l0 to 100 C., preferably about 30 C. and pressures of 04,000 psig, preferably 0-600 psig, say 60 psig, during a period of l-300 minutes, preferably 3-60 minutes, say 15 minutes.

At the end of this period, polymerization may be found to be complete. The catalyst may be deactivated as by addition of an alcohol such as isopropanol or butanol. The mixture may be deashed by mixing with aqueous hydrochloric acid; and the organic layer may be separated and stripped to yield a residue of copolymer. The copolymer may be obtained in an amount of [-10 parts, say 5 parts corresponding to percent to 98 percent, say 97 percent yield based on ethylene.

The polymer of this invention may contain two components or three components. When it is a two-component copolymer, preferably the ethylene component may be present in amount of 20-85 parts, preferably 50-80 parts, say 70 parts, and the higher alpha olefin, preferably propylene, may be present in amounts of 15-80 parts, preferably 20-50, say 30 parts. When it is a terpolymer, preferably the ethylene component may be present in amounts of 20-85 parts, preferably 50-80 parts, say 70 parts, the higher alpha olefin component may be present in amounts of 15-80 parts, preferably 20-50 parts, say 30 parts, and the third component, typically 5-ethylidene-2-norborncne, may be present in amounts of -25 parts, preferably 0.5-1 parts, say 3 parts. Other copolymerized monomers may also be present including butene-l, etc. The product may typically have a number average molecular weight M of 5(),0()0-200,000 as determined by osmometry.

The novel terpolymer produced by the process of this invention may have a desirably high number average molecular weight as high as 200,000 in contrast to typical prior art terpolymer values of 50,000-60,000 or lower and the typical control polymer values of 70,000-100,000. This factor is important because it contributes to tensile strength of the polymer.

The tensile strength of the product may be found to be about to 20 percent above typical comparable prior art values.

It is a particular feature of the product of this invention that it may be formulated and compounded to produce a product which is unexpectedly characterized by an extrusion rate which may be 5 to percent greater than the extrusion rate of the best commercially available comparable products presently known. This is a significant improvement in that it directly means that product can be extruded at substantially high rates than has heretofore been possible.

The product may readily be blended with a variety of oils, carbon blacks, clays and silicas. Typical carbon blacks may include those commercially available under the designations SAF, SRF, HAF, FEF, and MPC. The carbon black in amounts of 0-500 or more, preferably 0-200 parts by weight,

may be blended with 100 parts of polymer; and 0-200 parts of oil may also be added.

An additional unusual feature of this invention is that the copolymer produced with the novel catalyst may be cured to high tensile strength even in the presence of carbon black filler having a large particle size. For example, tensile strength in excess of 900 psi may be obtained when the cured polymer contains 150-300 parts by weight of a coarse carbon black having an average particle size of 0. 1-0.5 microns and 50-150 parts of an extender oil.

The novel products of this invention may be used in a wide variety of end uses. Typically, they may find use in molded,

formed, or coated products including sponges, tires and inner tubes, footwear, cable coatings, hoses and tubings, belts, etc.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Practice of this invention may be illustrated by the following examples wherein, as elsewhere in this description, all parts are by weight unless otherwise indicated.

The polymerization may be carried out by passing to the polymerization reaction vessel per parts of diluent, 3.0 parts of ethylene, 8.0 parts of propylene, and 0.015 parts of the catalyst mixture in benzene, and 0.049 parts of diethyl aluminum chloride cocatalyst in a 2.8 percent (wt.) solution in hexane.

Reaction may be conducted at 30 C. and 60 psig for an effective residence time of 13.5 minutes during which the reactants may be subjected to agitation. All reactants and vessels may be maintained pure, dry and anaerobic.

At the conclusion of a polymerization run, the products may be removed from the reaction vessel and the catalyst deactivated by addition of 0.5 parts of isopropanol. The reaction mixture may be mixed with dilute hydrochloric acid and the hydrocarbon layer separated. Solvent may be stripped at 100 C. to yield product polymer.

The product may be analyzed and the analyses are set forth in Table Ill together with other significant process conditions.

The specific process conditions set forth in the various tables may include the following:

1. Al/V+Ti The molar ratio of the aluminum cocatalyst to the sum of the moles of the vanadium catalyst and the titanium catalyst.

2. Rate The rate of polymerization in grams per hour was also determined.

3. Efficiency The catalyst efficiency was determined in terms of pounds of polymer produced per pound of VCl present in the catalyst.

4. Conversion The percent of ethylene and separately the percent of propylene admitted to the reaction vessel, which was converted to polymer product, was measured.

5. C Comp. The weight percent of ethylene in the polymer composition was measured by infrared spectroscopy.

6. I.V. The inherent viscosity of the polymer product was determined in decalin at C. by standard methods.

7. M The Mooney Viscosity at 260 F. was determined using a large No. l rotor for 8 minutes.

In Table III which follows, the results of Example 1 are set forth. In Examples 2-15, the same conditions as used in Example l were followed except where, as shown, the ethylene feed or the propylene feed or the ENB feed or the catalyst quantity or the A1/V+Ti ratio was changed. In run 15, the ratio of vanadium to titanium was changed, as will be discussed hereafter. All reactions were carried out at 25 C., except Examples 1, 2, and 3 which were carried out at 30 C. The residence time in all cases was about 13.5 minutes.

TABLE III Ex. Feed 1b./100 lbs. Diluent Solvent No. Ethylene Propyl- ENB Catalyst Al/V-l-Ti ene The results obtained from the calculations and analyses are as set forth in Table IV.

7 8 TABLE IV the tensile strength of applicant's novel product may be 10 percent to 15 percent higher than that ofthe control prior art Emmph, Em q f l lf i product. Similarly, the elongation of applicants novel product Numlm 1411- cir-ucy fi r may be 5 to 10 percent greater than that of the control prior 1'45 605 H5 7 1 75 5 5 art product. More unexpectedly, however, is the fact that it is {225 possible to simultaneously increase both the tensile strength 1143 500 :13 10. 1 03.0 3.3 1;. and the percent elongatlon. Prior attempts to increase one of these properties normally results in a decrease in the other. 031 537 01.5 10.4 01.0 3.0 I 59 Also apparent is the fact that the 300 percent modulus,

""6; 10 which is a measure of the strength of the product, may be in- 1,411.5 1523 .13 21.1 5 .1 -i creased by roughly the same order of magnitude as the im- 1.20r; -27 :10. 5 20.3 73. 2. n5 5, mg! 485 provement 1n tensile strength. 1t 15 unexpectedly also found 5 that the rate of extrusion may be increased by a factor of as 55;. 'llll 16:1 11 1 31. 5 much as 10 percent, this being a very significant commercial factor.

From Examples 1-15 as tabulated in Tables [11 and 1V, it lnspction of the last three columns of the above table will be apparent that over the various conditions under which (wherem factors l' the same except for [he Chfmge m the examples were carried out and at the varying ratios of aluthe mole 9 of the catfflystl f l P usfng the minum to vanadium and titanium, the rate of copolymeriza- 20 novfel lechfllque of the "15mm mvemwnr P 2 10 ion was if ml high [I ranged f a minimum f 3 2 ach1eve satisfactory results over a comparably wide variatlon grams of copolymer produced per hour at the lowest up to, in catalyst composmonthese illustrative examples, 1,495 grams per hour. Further- Results comparable to the above y be Obwmed l 8 more, as will be noted from column 3 of Table IV, the catalyst other l' Systems falling Within the scope of invenefficiency may uniformly be at the 500-600 pound per pound lion, for example; level. It will also be noted from Table N that unusually high Vanadlunl tetrachloride conversion yields of ethylene may be obtained; and in fact in tetrabutyl tltanate Example 12, 100 percent conversion was obtained. toluene The number average molecular weight M, of the product of van dium tetrachloride Example 3 was determined and found to be 113,000. It is tetrabutyltitanate highly unexpected that a composition having a Mooney ethyl benzene Viscosity of 41 should have a high number average molecular c. vanadium tetrabromide weight. A product prepared by prior art processes having a tetrabutyl titanate Mooney Viscosity of this value would normally be expected to benzene have a number average molecular weight of 60,000 to 70,000. d di hl id The products of Examples 2, 3, 13, 14 and 15 supra, which tetrapropy] manme are typical of the polymer compositions prepared in acxy|ene cordance with the process of this invention, were each A f h pair f comparative examples may be Carried out ep y compounded y mixing with the following formulain the first (Example 16 i of which 19.3 parts of vanadium OHS: tetrachloride may be mixed with 17 parts oftetrabutyl titanate TABLE V in 174 pans of toluene aromatic solvent.

A second control experiment (Example 17) may be carried out under identical conditions except that the vanadium Pan's tetrachloride and the tetrabutyl titanate are mixed in n-hexanc Polymer 100 FE}:- Carbon Black 00 rather than 1n toluene. MT Carbon Black 100 In a third control (Example 18) the mixing was carried out Flexon 880 Blend of Extender Oil 120 in cyclohexanc g ir -ii gxlli e It will be observed that the catalyst system of Example 16 TMTDS (tetramethyl thiuram may be formed with liberation of heat (raising the temperadisulfidc) 3 ture from 27 C. up to 48.5 C.) and the formation of a subggigjmercapwbenzmhlazolc) stantially homogeneous solution. in contrast, the systems of Examples 17 and 18 may quickly turn black with formation of a hard lumpy precipitate which is unsuitable for use in a The ix d f r ul ion a b bl nd d i a B b homogenous catalysis, and which in fact may possess substanmixer, then cured for 20 minutes at 320 F. and tested in stani lly n0 catalytic activity. dard manner. The products of hi i nti wh te d Although this invention has been illustrated by reference to against the Nordel brand of ethylene-propylene copolymer (:1 specific embodiments, it will be apparent to those skilled in comparable brand presently marketed) as a control, may be the art that various changes and modifications may be made found to possess the properties set forth in Table VI as follows: which clearly fall within the scope of this invention.

TABLE \'I Control Example 2 Example 3 Example 13 Example 14 Exampl 15 M 40 41 41 37 31 35 w 'ght percent 50.0 59.8 60.0 57.0 50.0 02.0 V/Ti mole ratio. 2 .r 2 1. 3 1

Physical propert T 1,200 1,320 1,370 1,300 1,300 1,130 Elongation, pc 305 335 310 350 310 310 1,180 1,%0 1,320 1,150 1,200 1,400 83 92 88 s5 s0 03 From the above table it will be apparent (comparing the What i C im d 1 control prior art with Examples 2 and 3 carried out in accordance with the instant invention) that the products are comparable products in that they have essentially the same M (Mooney Viscosity) and percent ethylene. However, inspection of the measured physical properties clearly reveals that 1. A process for preparing a copolymer of ethylene and a C- to C higher alpha olefin which comprises:

a. forming a charge mixture of ethylene and a C to C higher alpha olefin; b. forming, in an aromatic hydrocarbon solvent in the absence of cocatalyst, a catalyst mixture consisting essentially of from 1 to 10 moles of VX wherein X is a halide having an atomic number greater than 9, and from 0.5 to

5.0 moles of Ti(OR) wherein R is an alkyl hydrocarbon moiety having from I to l carbon atoms, thereby forming a catalyst component of the formula VX,'bTi(OR);- nA, wherein b is 0.1 to 5.0, n is 0.5 to 3.0, and A is said aromatic hydrocarbon;

contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst component in said aromatic hydrocarbon solvent and of (ii) as cocatalyst, a compound R',,AlY;, wherein R is a hydrocarbon moiety, a is an integer 1-3, and Y is a halide having an atomic number greater than 9;

. copolymerizing said charge mixture at a temperature in the range of about -l0 to 100 C. and at a pressure in the range of about 0 to 1,000 psig, thereby forming a copolymer of ethylene and a C C alpha olefin; and

e. withdrawing said copolymer as product. 2. The process claimed in claim 1 wherein said aromatic hydrocarbon solvent is benzene.

3. The process claimed in claim 1 wherein said VX is vanadium tetrachloride.

4. The process claimed in claim 1 wherein said Ti(OR),, is tetrabutyl titanate.

5. The process claimed in claim 1 wherein said cocatalyst is diethyl aluminum chloride.

6. A process for preparing a curable, elastomeric copolymer of ethylene and a C to C, alpha olefin which comprises:

a. forming a charge mixture of ethylene and a C to C,

higher alpha olefin; Y b. forming, in an aromatic hydrocarbon solvent in the absence of cocatalyst, a catalyst component consisting essentially of vanadium tetrachloride and tetrabutyl titanate having the formula VCl 'bTi(O-butyl) 'nA, where b is 0.1 to 5.0, n is 0.5 to 3.0, and A is said aromatic hydrocarbon; c. contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst component in said aromatic hydrocarbon solvent and of (ii) as cocatalyst, a

compound R AlY wherein R moiety, a is an integer 1-3, and Y is atomic number greater than 9;

d. copolymerizing said charge mixture at a temperature in the range of about l0 to C. and at a pressure in the range of about 0 to 1,000 psig, thereby forming a copolymer of ethylene and a C C, alpha olefin; and

e. withdrawing said copolymer as product.

7. The process of preparing a copolymer of ethylene and a C;, to C higher alpha olefin as claimed in claim 1, wherein said catalyst component in said aromatic hydrocarbon solvent is added to said reaction zone separately from said cocatalyst.

8. The process of preparing a copolymer of ethylene and a C to C higher alpha olefin as claimed in claim 1, wherein said catalyst component in said aromatic hydrocarbon solvent is added to said reaction zone separately from said cocatalyst and with said ethylene and said C to C higher alpha olefin.

9. A process for preparing a copolymer of ethylene, a C to higher alpha olefin, and a nonconjugated diolefin which compnses:

a. forming a charge mixture of ethylene, a C to C alpha olefin and a nonconjugated diolefin;

b. forming, in benzene in the absence of cocatalyst, a catalyst mixture consisting essentially of from 1 to 10 moles of vanadium tetrachloride and 0.5 to 5.0 moles of tetrabutyl titanate thereby forming a catalyst component of the formula VCl -bTi(O-butyl),'n benzene, where b is 0.] to 5.0 and n is 0.5 to 3.0;

c. contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst component in benzene and of (ii) diethyl aluminum chloride as cocatalyst;

d. copolymerizing said charge mixture at a temperature in the range of about l0 to I00 C. and at a pressure in the range of about 0 to 1,000 psig, thereby forming a terpolymer of ethylene, a C to C alpha olefin, and a nonconjugated diolefin;

e. withdrawing said terpolymer as product.

is a hydrocarbon a halide having an higher 

2. The process claimed in claim 1 wherein said aromatic hydrocarbon solvent is benzene.
 3. The process claimed in claim 1 wherein said VX4 is vanadium tetrachloride.
 4. The process claimed in claim 1 wherein said Ti(OR)4 is tetrabutyl titanate.
 5. The process claimed in claim 1 wherein said cocatalyst is diethyl aluminum chloride.
 6. A process for preparing a curable, elastomeric copolymer of ethylene and a C3 to C10 alpha olefin which comprises: a. forming a charge mixture of ethylene and a C3 to C10 higher alpha olefin; b. forming, in an aromatic hydrocarbon solvent in the absence of cocatalyst, a catalyst component consisting essentially of vanadium tetrachloride and tetrabutyl titanate having the formula VCl4.bTi(O-butyl)4.nA, where b is 0.1 to 5.0, n is 0.5 to 3.0, and A is said aromatic hydrocarbon; c. contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst component in said aromatic hydrocarbon solvent and of (ii) as cocatalyst, a compound R''aAlY3 a wherein R'' is a hydrocarbon moiety, a is an integer 1-3, and Y is a halide having an atomic number greater than 9; d. copolymerizing said charge mixture at a temperature in the range of about -10* to 100* C. and at a pressure in the range of about 0 to 1,000 psig, thereby forming a copolymer of ethylene and a C3-C10 alpha olefin; and e. withdrawing said copolymer as product.
 7. The process of preparing a copolymer of ethylene and a C3 to C10 higher alpha olefin as claimed in claim 1, wherein said catalyst component in said aromatic hydrocarbon solvent is added to said reaction zone separately from said cocatalyst.
 8. The process of preparing a copolymer of ethylene and a C3 to C10 higher alpha olefin as claimed in claim 1, wherein said catalyst component in said aromatic hydrocarbon solvent is added to said reaction zone separately from said cocatalyst and with said ethylene and said C3 to C10 higher alpha olefin.
 9. A process for preparing a copolymer of ethylene, a C3 to C10 higher alpha olefin, and a nonconjugated diolefin which comprises: a. forming a charge mixture of ethylene, a C3 to C10 higher alpha olefin and a nonconjugated diolefin; b. forming, in benzene in the absence of cocatalyst, a catalyst mixture consisting essentially of from 1 to 10 moles of vanadium tetrachloride and 0.5 to 5.0 moles of tetrabutyl titanate thereby forming a catalyst component of the formula VCl4.bTi(O-butyl)4.n benzene, where b is 0.1 to 5.0 and n is 0.5 to 3.0; c. contacting said charge mixture in a reaction zone with a catalytic amount of (i) said catalyst component in benzene and of (ii) diethyl aluminum chloride as cocatalyst; d. copolymerizing said charge mixture aT a temperature in the range of about -10* to 100* C. and at a pressure in the range of about 0 to 1,000 psig, thereby forming a terpolymer of ethylene, a C3 to C10 alpha olefin, and a nonconjugated diolefin; e. withdrawing said terpolymer as product. 